Rotary power device

ABSTRACT

A rotary power device, such as a pump or motor, comprises a central rotor member with a shaft mounting the rotor member for rotation about the axis of the shaft, a plurality of vane members carried by the rotor member and arranged to move in planes parallel to, preferably intersecting, the shaft axis, and a stator member surrounding the rotor member and including lobed surfaces which are complementary so that the vane members follow such surfaces during rotation of the rotor member. The stator member is provided with appropriate inlet and outlet ports for admitting and exhausting a working fluid from regions of the chamber defined between the lobed surfaces, the inner and outer side walls of the stator member, and the vanes and supporting walls of the rotor member. The vane members are spaced around the rotor member such that at least one vane is always positioned between the inlet and outlet ports. Each vane member includes separate vane parts following each of the lobed surfaces and loosely joined by a wedge-like key having angled surfaces which are arranged to press the vane parts toward the lobed surfaces as centrifugal force tends to move the key radially outward. The device can be employed as a rotary motor, engine, or pump, using either compressible or noncompressible fluids.

United States Patent 1191 Burrowes 1451 Sept. 2, 1975 1 1 ROTARY POWERDEVICE [76] Inventor: David E. Burrowes, 4466 Silverwood, Dayton, Ohio45429 [22] Filed: Apr. 4, 1974 [2]] App]. No.: 457,751

52 us. c1. 418/111; 418/148; 418/219; 418/230; 123/833 51 n11.c1. F01C1/00; F03C 3/00; F04C 1/00; F01C 19/08 [58] Field of Search 418/13, 111,219, 228-231, 418/148; 123/833, 8.35, 8.23, 8.41

Primary Examiner 1ohn .1. Vrablik Attorney, Age/1!, 0r FirmBiebel,French & Bugg l lhl [57] ABSTRACT A rotary power device, such as a pumpor motor, comprises a central rotor member with a shaft mounting therotor member for rotation about the axis of the shaft, a plurality'ofvane members carried by the rotor member and arranged to move in planesparallel to, preferably intersecting, the shaft axis, and a statormember surrounding the rotor member and including lobed surfaces whichare complementary so that the vane'members follow such surfaces duringrotation of the rotor member. The stator member is provided withappropriate inlet and outlet ports for admitting and exhausting aworking fluid from regions of the chamber defined between the lobedsurfaces, the inner and outer side walls of the stator member, and thevanes and supporting walls of the rotor member. The vane members arespaced around the rotor member such that at least one vane is alwayspositioned between the inlet and outlet ports. Each vane member includesseparate vane parts following each of the lobed surfaces and looselyjoined by a wedge-like key having angled surfaces which are arranged topress the vane parts toward the lobed surfaces as centrifugal forcetends to move the key radially outward, The device can be employed as arotary motor, engine, or pump, using either compressible ornoncompressible fluids.

4 Claims, 9 Drawing Figures 1 I I I [I1 PATENTEDSEP 2mm 3.902.829

SHEETILUFB M FIG-1 as PATENTED SEP 19 5 SHEET 2 BF 3 ROTARY POWER DEVICEBACKGROUND OF THE INVENTION This invention relates to rotary powerdevices of the class utilizing reciprocating vanes as part of themechanism for controlling the in-flow and exhausting of a working fluidfrom a chamber which increases and decreases in volume. In the wellknown types of sliding vane devices, a rotor is provided with slots orother suitable mounting arrangements for vanes which extend radiallyfrom the rotor into contact with the walls of an outer chamber. and theaxis of rotation of the rotor is eccentric with respect to the outerchamber, the vanes move in a generally radial direction to defineregions or chambers which increase or decrease in volume as the motionof the rotor and/or the outer member, progresses. It is well known thatsuch devices have various sealing problems, particularly along the wallsof the sliding vanes. and by their nature they are somewhat out ofbalance in rotation due to the generally radial movement of the vanemembers.

Another form of rotary power device, sometimes referred to as a barrelmotor, involves the use ofa plurality of cylinders spaced around an axisof rotation, and a plurality of pistons operating in those cylinders andconnected to a wobble plate which extends at a transverse angle to theaxis of rotation and is connected to the pistons such that theyreciprocate longitudinally in the cylinders as the wobble plates rotate.In such an arrangement it is necessary that both the cylinder and pistonmembers rotate, or else that there be some indirect connection betweenthe pistons and the wobble plate such that these parts can move relativeto each other.

A further class of rotary powered devices involves the more recentlydeveloped Wankel engine, utilizing a three or more sided rotor whichrotates within a specially formed chamber. both about the axis of therotor, and with that axis also rotating within the chamber. The sealingproblems of such devices, and the complexity of the machining operationsfor forming the various surfaces, are well known and have been thesubject of considerable recent discussion and development work.

SUMMARY OF THE INVENTION The present invention provides the advantagesof continuous rotary motion, and utilizes the centrifugal forcesinvolved with the moving parts of the device to promote scaling contact,particularly between the vane members of the device and the wallsagainst which these vane members track. The device preferably is formedas a double-acting motor or pump, since such an arrangement is mostconvenient to provide in accordance with the basic arrangement of parts.

A plate-like rotor member is mounted to rotate with a main shaft,extending outwardly from the main shaft and provided with slots in whichvane members are retained in reciprocating motion in planes which areparallel to the shaft axis, preferably intersecting such axis. Onopposite sides of the rotor member there are lobed stator parts whichare formed with cam-like lobes, one complementary to the other. suchthat the vane members follow the lobe surfaces of these stator membersand reciprocate along the aforementioned planes. The only reciprocatingmovement, therefore. of rotating parts is in a direction parallel to theshaft, and there is no reciprocation or movement toward and away fromthe shaft axis, thus minimizing the substantial efi'ect of centrifugalforces, and opposition thereto, on the rotating parts of the device. Forexample, there is a much less stringentsize and weight limitation,particularly at high speeds (e.g., over 5,000 rev./min. than is presentin the radially moving sliding vane motor.

The stator members also provide an inner wall against which the inneredges of the vane members track with both a circular and reciprocatingmotion, and a surrounding cylindrical casing provides a tracking surfaceand enclosure for the outer edges of the vane members'Preferably, thevane members comprise independent pieces loosely joined by a wedge-likekey, so that when one-vane member follows a rise or lobe of a camsurface, -it imparts motion through the connecting key against the othervane member, causing it to follow the valley or depression of the lobedsurface. These keys are provided with an angled edge such thatcentrifugal force tending to move the key radially outward, presses uponthe vane members and their seal parts and promotes sealing against thesurfaces which the vane members follow. The vane members follow theinner and outer chamber walls in circular fashion, thus the sealnecessary at those contact edges between moving parts is a relativelysimple seal, and may be provided in many cases merely by close machiningtolerances. However, a construction for enhancing the sealing of thevane members to the inner chamber walls is also provided as an option ifdesired. The. same is true of the seals required between the vanemembers and the rotor slots within which they reciprocate. The amount ofreciprocating movement can be relatively slight to achieve a ratherlarge displacement, since significant enlargement or displacement can beachieved merely by increasing the diameter of the rotor and stator partssomewhat, and increasing the width of the vane members.

When operating with an elastic working fluid, such as steam or hot gasproducts of combustion, it may be desirable to providesome valvingcontrol of the working fluid, particularly-to the inlet ports of thedevice. This can readily be achieved by the use of rotating ported valveplates fastened to the shaft and rotating with it, on the outer sides ofthe lobed stator members, or by the use of multi-part ported vanemembers.

Also, by changing the contour of the lobed surfaces, it is readilypossible to change the rate of expansion of compressible working fluids,and to match this and the rate of compression (if used) to a particulartype of fluid, or fluid mixture such as fuel/air.

Accordingly, the primary object of the invention is to provide a novelrotary power device, useful as a pump or motor, which is of relativelysimple and inexpensive construction, and which is characterized by thefact that it has vane members which reciprocate only in directionsgenerally parallel to the axis of rotation, which do not reciprocatetoward and away from the axis of rotation, yet provide adequate sealingbetween rotating parts by utilizing centrifugal force on rotating partsto emphasize sealing contact between relatively moving parts; and toprovide such a device which is relatively simple in construction, andmay be manufactured with relatively straightforward and inexpensivemachining operations.

Other objects and advantages of the invention will be apparent from thefollowing description, the accompanying drawings and the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view of a motorincorporating the features of the invention, with the outside case ofthe motor shown in cross section, and the shaft and internal parts shownin elevation;

FIG. 2 is a view similar to FIG. 1, but with only a part FIG. 7 is apartial cross-sectional view taken on lines 77 of FIG.

FIG. 8 is a view of another modification; and FIG. 9 illustrates amodified vane member.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1-3, themotor is comprised of a case which includes a cylindrical casing 10having outwardly extending flanges 12 at its opposite ends, and endplates 14 which are fastened by bolts 15 to the flanges 12. In thecentral part of each end plate 14 there is a bearing 17, shown in theform of a suitable roller bearing, which supports the main shaft forrotation about an axis which is concentric with the longitudinal axis ofthe cylindrical case. Suitable seals 22 and 23 are placed between theend plates 14 and shaft 20, and between the end plates 14 and theinternal wall of the cylindrical casing 10.

The rotor section of the motor comprises a central hub 25 which is fixedto the shaft 20, for example by a spline 26, or equivalent connection.This hub has spaced outwardly extending flanges 27 which extendoutwardly into close running tolerance with the internal wall of thecasing part 10, and these flanges are provided with vane slots 30 whichreceive vane assembly 32. These are particularly visible in FIG. 3. Thevane assemblies include a pair of individual vane members 33 and aconnecting rib or key member 34 which appears in greater detail in abroken-away portion at the bottom of FIG. 2. It will be noted that thiskey member, is somewhat tapered, as are the slots 35 internally of theroot portion of the vanes into which the key member projects. When themotor is operating centrifugal force causes the tapered key members 34to press outwardly, causing the vane members 33 to separate somewhat ina direction longitudinally of the motor (parallel to the shaft) forsealing purposes, as is later explained.

The stator parts of the motor include a pair of complementary stator cammembers and 42 which are essentially mirror images of each other. Theyfit within the casing member 10, and are fastened thereto by bolts 43 asshown in FIGS. 1 and 2. They may comprise a unitary piece, or as shown,for purposes of simplified construction, they may be made of a centralpart 4011 and 4211 which is essentially a counter bored cylinder, andthe surrounding ring-like cam members 40b and 4212. These parts may besuitably attached to one another by any suitable means, not shown. Eachof the stator members presents an essentially flat circular face towardthe outer ends of the motor, and there its inner face is formed in theshape of a circular cam. This cam surface is indicated particularly inFIG. 3 as including a pair of lobes 42c, and there are similar lobes 400(FIG. 1) formed on the stator cam member 40.

The lobes on one cam are aligned with the depressions or valleys on theother cam, so that the two cams define between them a space which thevane assemblies 32 sweep or displace as the rotor rotates within theeasing. Thus, between the facing walls of the stator member, throughwhich portions of vane members 33 project, and the opposing faces of thecam surfaces of the stator assemblies, there are defined chambers whichhave regions of larger and smaller volume, progressing around thecasing, as shown in generated form in FIG. 6. The tips or edges 33a ofthe vane members sweep the cam surfaces as the vanes rotate with therotor. It will be noted particularly in FIGS. 1 and 6 that the vanemembers preferably present a tapered tip face so that a rather sharpsealing edge is presented on the vane member to engage with the camsurfaces of the stator member.

Various means such as insert strips or equivalent (not shown) can beused to perfect a seal at this edge. It is the only location in themotor where an essentially line contact is needed. The vane assembliesmove essentially as a unit, there being only a small amount of playbetween the individual vane members 33 and the key members 34 which holdthem in alignment and transmit thrust from one to another in a directionlongitudinally of the motor. The previously mentioned centrifugal forceon the key members causes them to tend to wedge the individual vanemembers 33 apart somewhat, promoting a good seal between the tip 33a ofthe vane members and the cam surfaces.

Within each of the lobes 40c and 420 there are inlet passages 50 andexhaust passages 52, the latter being upstream from the inlet passageswith respect to the direction of rotation of the rotor member, andpreferably including elongated port sections 53. As shown in FIG. 6, theinlet and outlet ports are spaced around the stator, and their spacingis somewhat greater than the distance between vane members 33, thusavoiding any direct flow of fluid between the inlet and outlet ports.

A fluid under pressure is admitted through the inlet passages 50 intothe expansion chamber which is defined by the trailing edge of a vanemember 33, the surface of the stator cam member 40 (or 42), the surfaceof the rotor flanges 27, and the inner and outer surfaces formed by thecentral parts 400 (or 42a) of the stator and the inner wall of thecasing 10.

In the case of an incompressible fluid, such as hydraulic fluid, thesupply of fluid under pressure to the inlets 50 may be continuous, withthe resultant force on the trailing sides of vane members 33 causing therotor member to rotate, until the vane members uncover the outlet ports52, whereupon the fluid is exhausted through the outlet port 52 and thisconnection continues as the vane members pass over the extended portsection 53. With the twin lobe structure shown, the effect is to havefour separate chambers operating, with a substantially continuous flowof hydraulic fluid through the motor. The stroke of each expansionchamber, can be compared to the stroke of a piston in a conventionalpiston-cylinder motor, and can be varied to suit different requirementsby changing the slope of the surfaces of the cam lobes and/or bychanging the number of such lobes around the stator member and thenumber of vane members,

The exhaust ports 52 are connected through suitable openings 54 in thesides of the casing 10, to which a suitable exhaust or return pipe canbe connected. This is particularly needed if hydraulic fluid should beused as the source of power, since it should be returned to a pump sumpfor recirculation.

In the event that the motor is to be used with an expansible fluid, suchas high temperature steam, it may be desirable to provide a valvingcontrol over the admission of such fluid to the inlet ports 50. In thatcase, the rotor member also includes a pair of valve plates 60 and 62,each suitably fastened to shaft 20, and each running respectively inclose-fitting relation to the outer or flat faces of the stator cammembers 40 and 42. These valve plates are provided with inlet controlports 64 that are aligned on a radius of the valve plate correspondingto the location of the stator inlet ports hausting the steam ascompletely. as possible through the outlet ports 52, and connecting thisexhaust to a suitable condenser (not shown). In order to assure completeexhaust, the port section 53 may be appropriately extended both upstreamand downstream from the port 52, as desired, in order to minimize anycompression of steam trapped in front of the vane'members. Similarly, itis possible to utilize other expansible fluids, for example hot gaseswhich might be the products of combustion of a continuously operatingburner, or air under pressure from a compressor or from heating to ahigh temperature by contact with some heat source externally of themotor.

In all cases, however, the major parts of the motor are required only torotate in a continuous fashion. Only the vane members reciprocate, andthis motion is along planes which extend parallel (preferably through)the axis of rotation of the motor shaft. The amount of reciprocation ofthe vane members is relatively slight for an engine of a givendisplacement. Centrifugal forces are employed in the vane assemblies topromote good sealing of the moving vane members to the surfaces againstwhich they run. All parts of the motor are relatively simple inconstruction, and may be machined and/0r cast effectively andinexpensively.

FIG. 9 shows a modified construction of vane members in which identicalparts have the same reference numbers as previously used. The vanemember has a longitudinal tapered passage 36 receiving a tapered pin 37which engages the key member 34. The inner edge of the vane member isfitted with a seal strip 38 which contacts a cross-pin 39. The cross-pinin turn is pressed by the tapered pin 37. Thus centrifugal force tendsto move both the vane member and key 34 to the left (as viewed), thewedge shape of the key pushes the vane member and pin 37 upward, and thepin pushes the seal strip 38 to the right via the cross pin 39.

In a typical device constructed generally as shown, using a lobularsurface of one inch in width and a rise in the order of one-half inch, afour chamber four vane motor having an outer diameter of somewhat lessthan 5 inches will displace. about 20 cubic inches per revolution. Thisallows for displacement lost due to the porting of the motor. v

In a larger single lobe (one each side) arrangement with two vane memberassemblies, it .is possible to achieve a total displacement of about-452cubic inches per revolution in a unit having a cam or lobular-surfacewith an outer diameter of 15 inches, an inner diameter of 9 inches,andvanemembers of 3 inch width moving longitudinally a total of 3inches. Thus substantial displacement can be achieved within arelatively small outer size of the unit.

Another modification is shown in FIG. 8, wherein one set of chambers isemployed for a compression function and the outer'set 'is'utilized foran internal combustion function. The chambe'rs are appropriatelyinterconnected by a dual vane arrangement 80, 81 including passages '82,83 formed in and through the vanes as shown. 4

One chamber 85 has an inlet port 86 connected to it. The advancingparallel vanes move over this port in relative positions such that thepassages 82, 83 are closed. Air (or mixture) ahead of the vane iscompressed. As the vanes slide into the outer chamber88, the passages82, 83 register and the compressed fluid transfers into chamber 88(behind blade 81 through a leaf-type check valve 89, or the like,controlling passage 83. As the blades continue to move, passages 82, 83are again closed and the mixture may be ignited by a suitable ignitor90. The force of the expanding, burning mixture reacts on the blades,and hence is transferred to the rotor structure. When the blades reachthe other end of the lobe, they pass anexhaust port 92 from chamber 88,and the products of combustion are exhausted while another charge isentering chamber 85. A

As previously explained, the number of chambers can be appropriatelymultiplied around the device. In this embodiment the uniflow arrangementof gases is achieved, and the device functions similarly to thefourcycle internal combustion process.

Utilizing a single lobe on each side, and a pair of dual-vane members180 apart, intake occurs in the lower chamber 85 while combustion istaking place in chamber 88. Mixture can be drawn in through a relativelylarge port 86, and the compression can be controlled by the length ofchamber 85 and the slope of its exit end 85a. The expansion of productsof combustion can be controlled by the length of chamber 88. Combustionoccurs behind a set of vane members while exhaust occurs through a largeport in front of the vane members, and with two sets of vane membersthis cycle happens twice per revolution.

Using this arrangement in a unit of the large dimensions stated above,an engine of about 226 cubic inch displacement can be provided in apackage size of roughly 18 by 18 inches.

While the forms of apparatus herein described constitute preferredembodiments of this invention, it is to be understood that the inventionis not limited to these precise forms of apparatus, and that changes maybe made therein without departing from the scope of the invention.

What is claimed is:

l. In a rotary power device, having a shaft defining a central axis,

a stator member including a pair of facing comple mentary lobularsurfaces extending radially outward around said shaft and spaced apartalong the axis of said shaft,

said surfaces terminating at inner and outer edges concentric with saidaxis,

an inner cylindrical wall mating with said inner edges and an outercylindrical wall mating with said outer edges,

a rotor member attached to said shaft extending radially outwardtherefrom between said surfaces and mating with said inner and outerwalls to form enclosed chambers which have progressively increasing anddecreasing cross-sectional size around said shaft along planes extendingradially from said axis,

spaced apart vane assemblies extending through said rotor member alongplanes which are parallel to said axis and extending generally outwardtherefrom into contact with said surfaces and said inner and outer wallsto divide said chambers into regions between said vanes which moveprogressively as said shaft and said divider member rotate with respectto said stator member,

and means defining ports opening into opposite ends of said chambers andcontrolled by movement of said vanes past said ports for supply andexhaust of a working fluid to and from said regions,

said vanes being spaced apart less than the spacing between those portsat opposite ends of said chambers to keep those ports separated at alltimes by a vane;

the improvement comprising:

each said vane assembly includes a pair of independent vane membershaving a tip contacting a corresponding one of said lobular surfaces anda root portion slidably supported in said rotor member, and a key memberengaging the root portions of the pair of vane members,

said key member and said root portions contacting along lines whichconverge radially outward of said rotor member whereby said key membertransmits thrust between the vane members and centrifugal force on saidkey member results in sealing force of said vane member tips againstsaid surfaces.

2. A rotary power device as defined in claim 1, including a rotary valvedriven member driven from said shaft and cooperating with the supplyport to control admission of an expansible fluid into said chamber.

3. A vane assembly for a rotary power device having cooperating innerand outer cylindrical walls and opposed complementary lobular surfacesextending between said walls forming a stator member, a rotary shaftextending concentrically of said stator member and a rotor member havinglaterally extending surfaces which mate with said walls and portions ofsaid lobular surfaces, said rotor member having a plurality of slotstherethrough, pairs of spaced apart vane members mounted for concurrentsliding movement along their length in said slots with the respectivetips of said vane members engaging and movable along said lobularsurfaces and with the inner and outer edges of said vane members movablealong said cylindrical walls, a wedge-shaped reaction key supportedbetween said vane members with a narrower edge located radially outwardof said rotor member, and complementary wedge surfaces on each of saidvane members engaging the associated key and providing a translation ofcentrifugal force on said keys into sealing forces urging the tips ofsaid vane members against said lobular surfaces.

4. A vane assembly for a rotary power device, comprising a pair ofspaced apart vane members mounted for concurrent movement along theirlength, a wedge shaped reaction piece supported between 'said vanemembers,

said vane members and said piece being adapted for simultaneous rotationin a direction such that centrifugal force is directed toward thenarrower edge of said piece,

seal strips carried on those edges of said vane members opposite to thenarrower edge of said piece, and means transferring force from saidpiece due to centrifugal force thereon into opposite forces tending tomove said strips away from the edges of said vane members on which saidstrips are carried.

1. In a rotary power device, having a shaft defining a central axis, astator member including a pair of facing complementary lobular surfacesextending radially outward around said shaft and spaced apart along theaxis of said shaft, said surfaces terminating at inner and outer edgesconcentric with said axis, an inner cylindrical wall mating with saidinner edges and an outer cylindrical wall mating with said outer edges,a rotor member attached to said shaft extending radially outwardtherefrom between said surfaces and mating with said inner and outerwalls to form enclosed chambers which have progressively increasing anddecreasing cross-sectional size around said shaft along planes extendingradially from said axis, spaced apart vane assemblies extending throughsaid rotor member along planes which are parallel to said axis andextending generally outward therefrom into contact with said surfacesand said inner and outer walls to divide said chambers into regionsbetween said vanes which move progressively as said shaft and saiddivider member rotate with respect to said stator member, and meansdefining ports opening into opposite ends of said chambers andcontrolled by movement of said vanes past said ports for supply andexhaust of a working fluid to and from said regions, said vanes beingspaced apart Less than the spacing between those ports at opposite endsof said chambers to keep those ports separated at all times by a vane;the improvement comprising: each said vane assembly includes a pair ofindependent vane members having a tip contacting a corresponding one ofsaid lobular surfaces and a root portion slidably supported in saidrotor member, and a key member engaging the root portions of the pair ofvane members, said key member and said root portions contacting alonglines which converge radially outward of said rotor member whereby saidkey member transmits thrust between the vane members and centrifugalforce on said key member results in sealing force of said vane membertips against said surfaces.
 2. A rotary power device as defined in claim1, including a rotary valve driven member driven from said shaft andcooperating with the supply port to control admission of an expansiblefluid into said chamber.
 3. A vane assembly for a rotary power devicehaving cooperating inner and outer cylindrical walls and opposedcomplementary lobular surfaces extending between said walls forming astator member, a rotary shaft extending concentrically of said statormember and a rotor member having laterally extending surfaces which matewith said walls and portions of said lobular surfaces, said rotor memberhaving a plurality of slots therethrough, pairs of spaced apart vanemembers mounted for concurrent sliding movement along their length insaid slots with the respective tips of said vane members engaging andmovable along said lobular surfaces and with the inner and outer edgesof said vane members movable along said cylindrical walls, awedge-shaped reaction key supported between said vane members with anarrower edge located radially outward of said rotor member, andcomplementary wedge surfaces on each of said vane members engaging theassociated key and providing a translation of centrifugal force on saidkeys into sealing forces urging the tips of said vane members againstsaid lobular surfaces.
 4. A vane assembly for a rotary power device,comprising a pair of spaced apart vane members mounted for concurrentmovement along their length, a wedge shaped reaction piece supportedbetween said vane members, said vane members and said piece beingadapted for simultaneous rotation in a direction such that centrifugalforce is directed toward the narrower edge of said piece, seal stripscarried on those edges of said vane members opposite to the narroweredge of said piece, and means transferring force from said piece due tocentrifugal force thereon into opposite forces tending to move saidstrips away from the edges of said vane members on which said strips arecarried.